SQL - DELETE Query

The SQL DELETE Query is used to delete the existing records from a table.

You can use WHERE clause with DELETE query to delete selected rows, otherwise all the records would be deleted.

Syntax:

The basic syntax of DELETE query with WHERE clause is as follows:

  DELETE FROM table_name  WHERE [condition];  

You can combine N number of conditions using AND or OR operators.

Example:

Consider the CUSTOMERS table having the following records:

  +----+----------+-----+-----------+----------+  | ID | NAME     | AGE | ADDRESS   | SALARY   |  +----+----------+-----+-----------+----------+  |  1 | Ramesh   |  32 | Ahmedabad |  2000.00 |  |  2 | Khilan   |  25 | Delhi     |  1500.00 |  |  3 | kaushik  |  23 | Kota      |  2000.00 |  |  4 | Chaitali |  25 | Mumbai    |  6500.00 |  |  5 | Hardik   |  27 | Bhopal    |  8500.00 |  |  6 | Komal    |  22 | MP        |  4500.00 |  |  7 | Muffy    |  24 | Indore    | 10000.00 |  +----+----------+-----+-----------+----------+  

Following is an example, which would DELETE a customer, whose ID is 6:

  SQL> DELETE FROM CUSTOMERS  WHERE ID = 6;  

Now, CUSTOMERS table would have the following records:

  +----+----------+-----+-----------+----------+  | ID | NAME     | AGE | ADDRESS   | SALARY   |  +----+----------+-----+-----------+----------+  |  1 | Ramesh   |  32 | Ahmedabad |  2000.00 |  |  2 | Khilan   |  25 | Delhi     |  1500.00 |  |  3 | kaushik  |  23 | Kota      |  2000.00 |  |  4 | Chaitali |  25 | Mumbai    |  6500.00 |  |  5 | Hardik   |  27 | Bhopal    |  8500.00 |  |  7 | Muffy    |  24 | Indore    | 10000.00 |  +----+----------+-----+-----------+----------+  

If you want to DELETE all the records from CUSTOMERS table, you do not need to use WHERE clause and DELETE query would be as follows:

SQL> DELETE FROM CUSTOMERS;  

Now, CUSTOMERS table would not have any record.